CP

More specifically, what do the decimal numbers here mean in relation to airflow and quicker vs slower spooling ability? I see numbers that vary widely on both sides from turbo to turbo.

An example:

T04E TURBOCHARGER

WET FLOATING BALL BEARINGS

1/8 NPT OIL INLET

T3 / T4 FOOTPRINT OK !!

SPECS:

.57T COMPRESSOR WHEEL

"STAGE III BRAND NEW"

T04 " O " T3/T4

.84 A/R TURBINE HOUSING
GREAT FOR RAPID SPOOL!

COMPRESSOR HOUSING A/R .50 TO4E

3" INLET


What are the specs on a K03, K04 and GT25 for comparison?

fusilier

T04 is a family of turbos from Garrett. Specifically its a compressor wheel which is the cast aluminum wheel on the intake which draws the air into the compressor housing.

Wet floating ball bearings is a type of center section which supports the shaft of the turbo. Turbos have 4 main components. Coldside housing, Center bearing section, Hotside housing and shaft with wheels. The shaft floats, spins and bears completely within the center section.

1/8" NPT. NPT is national pipe thread. Its a plumbing standard with recognizable tapered threads suitable for threading together pipe to seal for fluids. Its use is initially for threading together black gas pipe and galv. water pipe in building construction. Its better than non-tapered threads for sealing. The 1/8" is the inside diameter of the pipe.

.57T compressor wheel. That number represents the dimensions of the compressor wheel relative to its top diameter and its bottom diameter. It is not 57%. It goes by the square. Within the same family of turbo, the bottom diameter of the wheel is usually the same. The top diameter is either smaller (lower trim) or larger (bigger trim). Larger seems better all the time, but its not cause that can create surge problems for big turbos on small cars.

T3/T4 are a family of Garrett turbos

StageIII in regards to Garrett refers to the turbine wheel itself. The turbine wheel is cast steel with the shaft. Its one piece. Stage III, STage V are different turbine wheels which go in the hotside and have different spool up vs high end characteristics.

A/R of turbine housing. Think of this number simplistically as a ratio betweeen the outlet size and the overall dimeter of the housing. SO big numbers like 1.3 mean the housing is large. Small numbers mean the housing is small which keeps the air pressure up and spools the turbine wheel faster. A .84 is reasonably small. Its tight and if you inspect the housing you'll see the air passage around the wheel is tight and close. A 1.3 housing will be cast so that the air passages around the wheel are much large. A 1.3 housing makes more high end flow for better top end HP, a .84 housing makes more low end spool up. Each family of turbo has its own family of associated hotside castings. For KKK turbos the Number of the housigin within a family is the A/R. For instance a K26 #8 housing is a .8 A/R.

Housing A/R is a descriptor of the scroll for the compressor housing. The compressor housing A/R effects the velocity of the air, the volume of the housing itself. It effects the compressor's efficiency similar to the hotside A/R.

3" inlet would mean the compressor wheel has a topside diameter of 3".

Hope thats usefull

Imolavirus@BuehnEngineering

" The turbine wheel is cast steel with the shaft. Its one piece. " The turbine wheel is made up of two pieces...a steel shaft and the inconel head. The two pieces are friction welded together.